diff --git a/include/fc/crypto/bigint.hpp b/include/fc/crypto/bigint.hpp
index e4fdd8b..debc869 100644
--- a/include/fc/crypto/bigint.hpp
+++ b/include/fc/crypto/bigint.hpp
@@ -11,7 +11,7 @@ namespace fc {
     public:
       bigint( const std::vector<char>& bige );
       bigint( const char* bige, uint32_t l );
-      bigint( unsigned long i );
+      bigint(uint64_t value);
       bigint( );
       bigint( const bigint& c );
       bigint( bigint&& c );
diff --git a/include/fc/network/tcp_socket.hpp b/include/fc/network/tcp_socket.hpp
index 2fd235e..f9dbce0 100644
--- a/include/fc/network/tcp_socket.hpp
+++ b/include/fc/network/tcp_socket.hpp
@@ -49,7 +49,7 @@ namespace fc {
       friend class tcp_server;
       class impl;
       #ifdef _WIN64
-      fc::fwd<impl,0x70> my;
+      fc::fwd<impl,0x78> my;
       #else
       fc::fwd<impl,0x4c> my;
       #endif
diff --git a/src/crypto/bigint.cpp b/src/crypto/bigint.cpp
index 0682992..b76ba92 100644
--- a/src/crypto/bigint.cpp
+++ b/src/crypto/bigint.cpp
@@ -6,6 +6,16 @@
 
 #include <fc/exception/exception.hpp>
 
+#ifdef _MSC_VER
+# include <stdlib.h>
+# define bswap_64(x) _byteswap_uint64(x)
+#elif defined(__APPLE__)
+# include <libkern/OSByteOrder.h>
+# define bswap_64(x) OSSwapInt64(x)
+#else
+# include <byteswap.h>
+#endif
+
 namespace fc {
       bigint::bigint( const char* bige, uint32_t l ) {
         n = BN_bin2bn( (const unsigned char*)bige, l, NULL );
@@ -28,9 +38,10 @@ namespace fc {
         return BN_dup( n );
       }
 
-      bigint::bigint( unsigned long i )
-      :n(BN_new()) {
-        BN_set_word( n, i );
+      bigint::bigint(uint64_t value)
+      {
+        uint64_t big_endian_value = bswap_64(value);
+        n = BN_bin2bn((const unsigned char*)&big_endian_value, sizeof(big_endian_value), NULL);
       }
 
       bigint::bigint( const bigint& c ) {
@@ -47,7 +58,15 @@ namespace fc {
       }
 
       bool bigint::is_negative()const { return BN_is_negative(n); }
-      int64_t bigint::to_int64()const { return BN_get_word(n); }
+      
+      int64_t bigint::to_int64() const
+      {
+        FC_ASSERT(BN_num_bits(n) <= 63);
+        size_t size = BN_num_bytes(n);
+        uint64_t abs_value = 0;
+        BN_bn2bin(n, (unsigned char*)&abs_value + (sizeof(uint64_t) - size));
+        return BN_is_negative(n) ? -(int64_t)bswap_64(abs_value) : bswap_64(abs_value);
+      }
 
       int64_t bigint::log2()const { return BN_num_bits(n); }
       bool bigint::operator < ( const bigint& c )const {